| Gaithersburg to Hanahan (South Carolina) | 456.07 mi (733.97 km) |
| Gaithersburg to Hanford (California) | 2,306.26 mi (3,711.57 km) |
| Gaithersburg to Hannibal (Missouri) | 757.13 mi (1,218.49 km) |
| Gaithersburg to Hanover (Pennsylvania) | 48.36 mi (77.84 km) |
| Gaithersburg to Hanover Park (Illinois) | 606.09 mi (975.40 km) |
| Gaithersburg to Happy Valley (Oregon) | 2,324.17 mi (3,740.39 km) |
| Gaithersburg to Harker Heights (Texas) | 1,278.81 mi (2,058.04 km) |
| Gaithersburg to Harlingen (Texas) | 1,483.74 mi (2,387.84 km) |
| Gaithersburg to Harper Woods (Michigan) | 376.08 mi (605.24 km) |
| Gaithersburg to Harrisburg (North Carolina) | 324.69 mi (522.54 km) |
| Gaithersburg to Harrisburg (Pennsylvania) | 80.72 mi (129.91 km) |
| Gaithersburg to Harrison (Arkansas) | 891.09 mi (1,434.06 km) |
| Gaithersburg to Harrison (New Jersey) | 196.52 mi (316.28 km) |
| Gaithersburg to Harrison (New York) | 226.14 mi (363.93 km) |
| Gaithersburg to Harrison (Ohio) | 405.51 mi (652.61 km) |
